it depends on company !!

1.some companies in Qatar are not expect resign letter only!!!

2.some will expect it after 1 month of running to manger to manger.

3. some expect resign letter and not give the knowledge , if u go ask HR they will say it is with dept.head...from months

4. some companies will expect it but not leave u for 2-3 or 4 months may long than that.

5.some will expect it and leave u but not pay the due salaries.

6.there are some good company one who follow the rule of law ,expect resign letter and leave you with in 1 month with all salary and benefits.

so u check u belongs to which company as mentioned above.